Recently, planar nonvolatile semiconductor memory devices have been close to the limit of miniaturization of memory cells. Thus, there are a number of proposals for next-generation memory devices in which memory cells are three-dimensionally arranged. Among them, the so-called cross-point memory is considered to be advantageous to increasing the degree of integration. The cross-point memory is a memory device in which memory cells are arrayed, each memory cell including a variable resistance element and connected to the intersection (cross point) of a word line and a bit line.
On the other hand, there are also proposals for memory cells, such as ferroelectric random access memory (FeRAM), magnetoresistive random access memory (MRAM), phase change random access memory (PCRAM), resistance random access memory (ReRAM), molecular memory, and conductive bridging random access memory (CBRAM). However, a cross point memory device including such memory cells is also made difficult to manufacture with the miniaturization of memory cells.